Spacer height

[Cat3roadracer]

What is the generally accepted max spacer height above the stem? Any opinions here?

Thanks.

[CPP]

I think it depends on how much stretching you plan to do!

Personally, I think 1.5 cm is the max (for my eyes)

[christian]

I run 1-1.5cm on top. I'm cheap and would like to re-sell my bike eventually. Yes, it looks crap.

[thirdgenbird]

In my opinion, It depends on the steerer and compression plug being used.

I wouldn't worry about spacers above the stem on a steel steerer. Some carbon steerers recommend (require) having the compression plug in line with the stem itself. Having too many spacers will make the plug higher than the stem.

My best recommendation would be to follow the fork's instructions. It should tell you spacer limits as well as the type of preload device that should be used.

[vintag3]

I usually just leave (1) 1.5mm spacer on my bikes, but that's only cause I dislike the look of having too many spacers above my stem:)

[dekindy]

I am assuming you are asking for safety. 30 is reasonably safe but 40+ is probably over the max for anybody.

IMHO more spacers is more pleasing looking that the extremely angled stems that I see regularly.

[pdmtong]

In my opinion, It depends on the steerer and compression plug being used.

I wouldn't worry about spacers above the stem on a steel steerer. Some carbon steerers recommend (require) having the compression plug in line with the stem itself. Having too many spacers will make the plug higher than the stem.

My best recommendation would be to follow the fork's instructions. It should tell you spacer limits as well as the type of preload device that should be used.

If your position is set then normally it's 1 cm above the stem to make sure the stem is no where near clamping at the end of the steerer.

If youwant to leave more for future proof or resale then do so at aesthetic risk.
I do. It looks like hell but oh well. Maybe I should take a lesson from jack or Ryun who slam stems but still are able to sell their frames

I don't agree the plug needs to be in line with the stem. You just want the Stem clamping away from the open end if the steerer and 1cm is generally recommended

[RedRider]

For personal bikes it's 0.5cm. More if I plan to sell in the near future.

[sales guy]

The maximum for safety as said by the carbon fork manufacturers total spacer stack is 35mm. Whenever I cut a fork, I allow for that with the stem on top. After that, the owner once a fit is done can choose what they wish to do. Cut the rest or spacer on top, But that's the max of spacers allowed or recommended from the manufacturers.

[echelon_john]

2 different questions being answered here.

OP asked how many spacers ABOVE the stem. For this, no max that I'm aware of. With a carbon fork, I would go minimum 2.5mm. The point is to have the entire stem clamping onto the carbon; not extending above it as you would need to in order to get preload tension from the top cap.

As far as maximum spacer height under the stem, it varies from manufacturer to manufacturer, but 30mm is a safe max number for carbon forks. With steel steerers you can go higher, as well as certain carbon forks (Z-Pro, for example).

[Ralph]

I'm putting a new Enve fork on a new custom steel frame soon. Gotta think about this same question. Normally, would just use one spacer above the stem, but may use 2 this time at first. Just want to ride the bike some before I settle in to final set up.

[wss]

The maximum for safety as said by the carbon fork manufacturers total spacer stack is 35mm. .......

Specialized and a few others I've seen have a 40mm max.
I do like their 48mm long expander plugs and use them on two of my bikes that I have 40mm of spacers.

http://search.yahoo.com/r/_ylt=A0oG7hZcftRSbxUAilZXNyoA;_ylu=X3oDMTEzaWg3cGw 0BHNlYwNzcgRwb3MDNwRjb2xvA2FjMgR2dGlkA1ZJUDI3MV8x/SIG=135b7g69d/EXP=1389686492/**http%3a//cdn.specialized.com/OA_MEDIA/pdf/manuals/08_Fork_Installation_Guide_r2.pdf

[pdmtong]

2 different questions being answered here.

OP asked how many spacers ABOVE the stem. For this, no max that I'm aware of. With a carbon fork, I would go minimum 2.5mm. The point is to have the entire stem clamping onto the carbon; not extending above it as you would need to in order to get preload tension from the top cap.

As far as maximum spacer height under the stem, it varies from manufacturer to manufacturer, but 30mm is a safe max number for carbon forks. With steel steerers you can go higher, as well as certain carbon forks (Z-Pro, for example).

ABOVE:
John is more eloquent than I. The recommended varies. I think enve says 1cm on top

BELOW:
typical response is 3.0-4.0cm on carbon steerer.

One reason to allow more room is variance in stem stack. Thomson X2 is 36mm...Moots Open Road is 45mm. Round off and you have a 10mm delta.

So before you cut, figure out your stem strategy too.

[thirdgenbird]

I don't agree the plug needs to be in line with the stem. You just want the Stem clamping away from the open end if the steerer and 1cm is generally recommended

Generally, but not always. Doesn't cannondale recommend no spacers above the stem?

[sales guy]

Specialized and a few others I've seen have a 40mm max.
I do like their 48mm long expander plugs and use them on two of my bikes that I have 40mm of spacers.

http://search.yahoo.com/r/_ylt=A0oG7hZcftRSbxUAilZXNyoA;_ylu=X3oDMTEzaWg3cGw 0BHNlYwNzcgRwb3MDNwRjb2xvA2FjMgR2dGlkA1ZJUDI3MV8x/SIG=135b7g69d/EXP=1389686492/**http%3a//cdn.specialized.com/OA_MEDIA/pdf/manuals/08_Fork_Installation_Guide_r2.pdf


The traditional rule for carbon forks is 35mm. Yes, there are a few out with 40. But I try not to fuss and worry if this fork or that is one of the 40's and just make everything 35 to make sure.

Steel fork, anything you want spacer stack wise.

As for gap, Aheadset, DIA Compe and Cane Creek all recommend between 3 and 5mm gap between the top of the fork and the top of the stem. I try for 3 usually. 5 works but no more than that for possible crunching of the fork.

Preferred stem tensioner is a wedge with a longer top cap that goes into the fork so stem tightening doesn't crush the fork. Something like the one Reynolds used to sell. If the fork has an internal wedge that uses a standard top cap with M6 bolt thru it, that fine. Like the one Alpha Q used to use. But the recommended spacer stack is still 35mm.

ATMO of course.

[p nut]

I was listening to some web hosted talk show a month or two ago, and they said anything over 40mm could be a detriment to the headset bearing. Any truth to this?

On my steel bike (with steel steerers), I have to run an unusual amount of spacers underneath as the headtube is tiny. I think 60mm, at least.

[Admiral Ackbar]

i don't doubt that a 4cm spacer stack would put more stress the hs bearings but I'm not sure it would be significant enough to worry about. and worse case, bearings cost like what, $40 at the most?

[thirdgenbird]

I wouldn't worry much about bearings either. Even if it cuts their life by 50%, I don't see a headset bearing spontaneously failing and causing an accident. If a bearing sounds or feels funny, replace it.

[shovelhd]

Zero. Slam it.